The Royal Navy was the first of the UK's armed services to induct into service the multi-purpose Merlin helicopter, this being the British military designation of what was the EH Industries EH101, now the AgustaWestland AW101. It did so in Merlin HM1 form, front-line operational capability being achieved in 2000. An upgrade programme is now under way, producing 30 examples of the HM2 version with enhanced mission systems and avionics. Anti-submarine warfare is the stock-in-trade of the Navy Merlins, for which role the type is armed with Sting Ray torpedoes. That aside, this is very much a multi-role helicopter, able also to perform general passenger and cargo transport, search and rescue, surface patrol, casualty evacuation and anti-piracy or anti-drug-running sorties. Four Naval Air Squadrons currently operate the Merlin, all from Royal Naval Air Station Culdrose in Cornwall; that at RIAT 2015 is due to come from 814 NAS. The fleet is being augmented by the addition of aircraft from the RAF's Merlin force, which are being transferred to the Navy.